The Biostatistics Core Facility for the Program Project is new to this revised application. The Biostatistics Core will provide services and collaboration to all investigators. This will enhance each project, better ensure the most effective design, computer data base management and use of statistical methods for integration and analyses of data. The Core will: 1) provide the statistical design of all projects, 2) provide quality assurance of data collection and data entry, 3) develop a coordinated computer data base management system to obtain and integrate data from all projects and cores, 4) provide biostatistical analyses of hypotheses, 5) work collaboratively with investigators to develop and prioritize multivariate, across project hypotheses, and 6) to develop and adapt statistical methods for analyses of multiple biologic markers in aggressive vs. non-aggressive skin cancer research.